In this spinoff of the true-crime megahit, an investigation of an alleged Alabama murder turned into a seven-part audio novel.

Years before the first season of “Serial” would cause a seismic quake in the podcasting world, “This American Life” producer Brian Reed got an unusual email.

Since he reports stories for one of the most popular programs on public radio, Reed gets a lot of emails. But, he notes, “not a lot of them come in with a subject line that says, ‘John B. McLemore lives in Shittown, Alabama.'”

So Reed gave McLemore a call and talked to him for hours: about the depression and racism that surrounded him in the state’s Bibb County; about climate change and larger, looming threats to the world that obsessed him; and about a local murder that he was absolutely certain had taken place, despite the lack of any available evidence.

During those conversations, McLemore proved himself to be such a bizarre and fascinating character that Reed started visiting him for reporting trips, to investigate the alleged murder, and to get to know the neighbors of “Shittown.” After three years of what executive producer Julie Snyder jokingly describes as “somewhat aimless” reporting and editing, Reed is spinning his material into the fascinating yarn that is “S-Town.”

“This American Life” is billing the new podcast as a “spinoff” to “Serial,” the hugely popular true-crime storytelling show that will launch its third season later this year. But unlike “Serial,” every episode of “S-Town” — seven in all, with the first two made available to IndieWire ahead of time — is being released at once on today’s launch day, Netflix-style.

Snyder, who is also an executive producer on “Serial” with host Sarah Koenig, said they try to choose the distribution model that suits the narrative. “The first season of ‘Serial’ was much more modeled off of a TV show,” she told IndieWire. “Whereas this one we were thinking more of a novel.”

As a novel, it made more sense to allow people to listen at their own pace. The approach also allowed a show with such a heavy emphasis on small-town rumors to take the time to respond to any accusations made by its sources.

And Reed has constructed “S-Town” with appropriately layered storytelling. He returns repeatedly to themes McLemore establishes early on, including his profession as a clock repairman, which becomes a throughline about how people choose to spend their time on Earth. Over the course of his investigation, he also detours to interview townspeople who work in lumber, or as tattoo artists, and airs the complexity of their characters in full — the sense of support they grant to fellow outsiders, combined with some deeply prejudiced views.

Once armed with all the audio at their disposal, Reed and Snyder retold the story to each other several times in order to get a feel for how to construct the narrative. That led Reed to a new realization.

“At points in the story, I’m going to know the future as the narrator,” he said. “That’s one of the powers of reporting a story for a year and a half. And it became apparent to us that we had this power accidentally.”

So Reed drew inspiration from novels like “The Known World,” by Edward P. Jones, which sprinkles small bits of foreshadowing throughout the narrative to hint at what happens to the characters.

“I hope people have an experience of it kind of like the way you have an experience with a good book,” Reed said. While noting he has nothing against people who “want to binge it all in one day,” he’s excited for people to fit it into their commutes or before-bed schedules. “It becomes this thing that’s hanging in your life as you’re going about your day-to-day life, this other world that’s with you, and these other people that are with you, embedding themselves in your skull.”

Everyone may be making podcasts these days, but the “This American Life” crew is one of the only shops that has found a way to turn the medium into real money. But they didn’t actually make that much money off of the 14 million average-per-episode downloads from the first season of “Serial.” Since the team had to line up ad sales before the first episode dropped, they couldn’t take financial advantage of the craze.

But, Snyder said, they were able to bring in a haul when they put out a call for donations tied to the first season. That provided enough funding for a second season of “Serial,” whose success then funded “S-Town,” which roped in sponsorships from podcast stalwarts Blue Apron and Squarespace.

If “S-Town” proves to be the next “Serial”-sized smash, Reed could be in for a deluge of requests from listeners begging him to come investigate their own local rumors.